It could be that the minions' social structure has some basis in reality. They have a hierarchy, like in real groups. Their search for a master could be related to how in nature, some animals follow a leader. For example, wolves follow an alpha. So the minions' loyalty to Gru in the movies might be a fun, exaggerated version of such real - life hierarchies.
Minions are these cute, yellow, and often clumsy characters. When we say they are based on a true story, it might be that their sense of community is inspired by real communities. They live together, work together, and get into all sorts of mischief together. This could be modeled after how in small villages or tribes, people rely on each other and have a shared existence. Also, their constant search for purpose, like serving a 'big bad' in the movies, could be a reflection of how people or animals in real - life situations often look for a role or a leader to follow.